diff --git a/.travis.yml b/.travis.yml
index 4119c6a..8f97b82 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -22,6 +22,7 @@ script:
   - "scripts/test-go-fmt.sh"
   - "gometalinter --vendor --deadline=60s --config=gometalinter.json ./..."
   - "go run cmd/main.go"
+  - "go test github.com/phase2/rig/util"
 
 notifications:
   flowdock:
diff --git a/cli/testing/assert.go b/cli/testing/assert.go
new file mode 100644
index 0000000..fe329f4
--- /dev/null
+++ b/cli/testing/assert.go
@@ -0,0 +1,38 @@
+// Code in this file originally copied from https://github.com/benbjohnson/testing
+// @see https://medium.com/@benbjohnson/structuring-tests-in-go-46ddee7a25c
+package testing
+
+import (
+	"fmt"
+	"path/filepath"
+	"reflect"
+	"runtime"
+	"testing"
+)
+
+// assert fails the test if the condition is false.
+func Assert(tb testing.TB, condition bool, msg string, v ...interface{}) {
+	if !condition {
+		_, file, line, _ := runtime.Caller(1)
+		fmt.Printf("\033[31m%s:%d: "+msg+"\033[39m\n\n", append([]interface{}{filepath.Base(file), line}, v...)...)
+		tb.FailNow()
+	}
+}
+
+// ok fails the test if an err is not nil.
+func Ok(tb testing.TB, err error) {
+	if err != nil {
+		_, file, line, _ := runtime.Caller(1)
+		fmt.Printf("\033[31m%s:%d: unexpected error: %s\033[39m\n\n", filepath.Base(file), line, err.Error())
+		tb.FailNow()
+	}
+}
+
+// equals fails the test if exp is not equal to act.
+func Equals(tb testing.TB, exp, act interface{}) {
+	if !reflect.DeepEqual(exp, act) {
+		_, file, line, _ := runtime.Caller(1)
+		fmt.Printf("\033[31m%s:%d:\n\n\texpected: %#v\n\n\tactual: %#v\033[39m\n\n", filepath.Base(file), line, exp, act)
+		tb.FailNow()
+	}
+}
diff --git a/cli/testing/testing.go b/cli/testing/testing.go
new file mode 100644
index 0000000..e299b1d
--- /dev/null
+++ b/cli/testing/testing.go
@@ -0,0 +1,122 @@
+// Testing package provides helpers to facilitate rig testing.
+// See additional documentation: https://gist.github.com/grayside/ffeb68fa342cecf1ec158c011cbd2ea3
+package testing
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"strings"
+	"testing"
+)
+
+// ExecMockSet provides a set of unique mocks. The key matches the remote execution script.
+type ExecMockSet map[string]string
+
+// ExecMockCollection is a map of ExecMockSets. The key is a category of mocks, such as
+// "success" or "notfound".
+type ExecMockCollection map[string]ExecMockSet
+
+var mock ExecMockCollection
+
+// SetMockValues provides an easy setter that allows the TestMain implementation
+// of individual test files to preload the potential values to use.
+func SetMockByType(namespace string, mockSet ExecMockSet) {
+	if mock == nil {
+		mock = make(ExecMockCollection)
+	}
+	mock[namespace] = mockSet
+}
+
+// TestMain is a special function that takes over handling the behavior of the the test runner `go test`
+// generates to execute your code. I do not know if you can have one per file or one for a project's entire
+// collection of tests.
+//
+// In the example below, we rely on an environment variable: `GO_TEST_MODE` to determine whether the
+// testing process will behave normally (running all test and handling the result, done by default) or
+// will behavior in a special manner because we have tailored the way an exec.Command() will execute
+// to flow through this logic instead of what was originally intended.
+//
+// You may be wondering, why would we go to such an elaborate length to mock the result of the a shell
+// execution? Well, if we directly interpolated the mocked value for the command, the resulting object
+// would be a string, and not the expected structure the code might be looking for as a result of executing
+// a remote command.
+//
+// To use this function, implement TestMain in your own class, then call:
+//
+// testing.MainTestProcess(m)
+func MainTestProcess(m *testing.M) {
+	switch os.Getenv("GO_TEST_MODE") {
+	case "":
+		// Normal test mode.
+		os.Exit(m.Run())
+
+	case "echo":
+		// Outputs the arguments passed to the test runner.
+		// This will be the command that would have executed under normal runtime.
+		// This mode can be used to test that we can predict programmatically assembled command that would be executed.
+		fmt.Println(strings.Join(os.Args[1:], " "))
+
+	case "succeed":
+		os.Exit(0)
+
+	case "fail":
+		os.Exit(42)
+
+	case "mock":
+		if mock != nil {
+			// Used the command that would be executed under normal runtime as the key to our mock value map and outputs the value.
+			// I am still researching how to adjust this overall pattern to centralize the code as test helpers but allow individual
+			// test files to supply their own mock.
+			fmt.Printf("%s", mock["success"][strings.Join(os.Args[1:], " ")])
+		}
+	}
+}
+
+// MockExecCommand uses fakeExecCommand to transform the intended remote execution
+// into something controlled by the test runner, then adds an environment variable to
+// the command so TestMain routes it to the command "mock" functionality.
+func MockExecCommand(command string, args ...string) *exec.Cmd {
+	cmd := fakeExecCommand(command, args...)
+	cmd.Env = append(cmd.Env, "GO_TEST_MODE=mock")
+	return cmd
+}
+
+// EchoExecCommand uses fakeExecCommand to transform the intended remote execution
+// into something controlled by the test runner, then adds an environment variable to
+// the command so TestMain routes it to the command "echo" functionality.
+func EchoExecCommand(command string, args ...string) *exec.Cmd {
+	cmd := fakeExecCommand(command, args...)
+	cmd.Env = append(cmd.Env, "GO_TEST_MODE=echo")
+	return cmd
+}
+
+// SucceedExecCommand uses fakeExecCommand to transform the intended remote execution
+// into something controlled by the test runner, then adds an environment variable to
+// the command so TestMain routes it to the command "success" functionality.
+func SuccessExecCommand(command string, args ...string) *exec.Cmd {
+	cmd := fakeExecCommand(command, args...)
+	cmd.Env = append(cmd.Env, "GO_TEST_MODE=success")
+	return cmd
+}
+
+// FailExecCommand uses fakeExecCommand to transform the intended remote execution
+// into something controlled by the test runner, then adds an environment variable to
+// the command so TestMain routes it to the command "fail" functionality.
+func FailExecCommand(command string, args ...string) *exec.Cmd {
+	cmd := fakeExecCommand(command, args...)
+	cmd.Env = append(cmd.Env, "GO_TEST_MODE=fail")
+	return cmd
+}
+
+// fakeExecCommand creates a new reference to an exec.Cmd object which has been transformed
+// to use the supplied parameters as arguments to be submitted to our test runner binary.
+// It should never be used directly.
+func fakeExecCommand(command string, args ...string) *exec.Cmd {
+	testArgs := []string{command}
+	testArgs = append(testArgs, args...)
+	cmd := exec.Command(os.Args[0], testArgs...)
+	cmd.Env = []string{}
+
+	return cmd
+}
diff --git a/cli/util/docker_test.go b/cli/util/docker_test.go
new file mode 100644
index 0000000..5da203d
--- /dev/null
+++ b/cli/util/docker_test.go
@@ -0,0 +1,96 @@
+package util_test
+
+import (
+	"testing"
+
+	rigtest "github.com/phase2/rig/cli/testing"
+	"github.com/phase2/rig/cli/util"
+)
+
+// mock provides mock values to use as lookup responses to functions we will execute in our production code.
+// The idea is to use the command as a lookup key to the result it might generate.
+// Currently it only supports a single value, in the future this may be split into multiple maps for different,
+// generic classes of success and failure. We cannot use multiple values for entries in this map because each response
+// is expected to be a string that an executed command would return to Stdout.
+var mockSet = rigtest.ExecMockSet{
+	"docker --version": "Docker version 17.09.0-ce, build afdb6d4",
+	"docker-machine ssh gastropod docker version --format {{.Server.APIVersion}}":    "1.30",
+	"docker version --format {{.Client.APIVersion}}":                                 "1.30",
+	"docker-machine ssh gastropod docker version --format {{.Server.MinAPIVersion}}": "1.12",
+	"docker inspect --format {{.Created}} outrigger/dust":                            "2017-09-18T21:43:00.565978065Z",
+}
+
+func init() {
+	rigtest.SetMockByType("success", mockSet)
+}
+
+// TestGetRawCurrentDockerVersion confirms successful Docker version extraction.
+func TestGetRawCurrentDockerVersion(t *testing.T) {
+	// In case some other functionality has swapped out this value, we will store
+	// it explicitly rather than assume it is exec.Command.
+	stashCommand := util.ExecCommand
+	// Re-define util.ExecCommand so our runtime code executes using the mocking functionality.
+	// I thought util.ExecCommand would be a private variable in file scope, apparently sharing the package
+	// is enough to access and manipulate it. Or perhaps test functions have special scope rules?
+	util.ExecCommand = rigtest.MockExecCommand
+	// Put back the original behavior after we are done with this test function.
+	defer func() { util.ExecCommand = stashCommand }()
+	// Run the code under test.
+	actual := util.GetRawCurrentDockerVersion()
+	rigtest.Equals(t, "17.09.0-ce", actual)
+}
+
+// TestGetCurrentDockerVersion confirms successful processing of Docker version into version object.
+// For more thoroughly commented exec wrangling details see TestGetRawCurrentDockerVersion.
+func TestGetCurrentDockerVersion(t *testing.T) {
+	stashCommand := util.ExecCommand
+	util.ExecCommand = rigtest.MockExecCommand
+	defer func() { util.ExecCommand = stashCommand }()
+	actual, err := util.GetDockerServerApiVersion("gastropod")
+	rigtest.Ok(t, err)
+	rigtest.Equals(t, "1.30.0", actual.String())
+}
+
+// TestGetDockerServerApiVersion confirms successful Docker client version extraction.
+// For more thoroughly commented exec wrangling details see TestGetRawCurrentDockerVersion.
+func TestGetDockerClientApiVersion(t *testing.T) {
+	stashCommand := util.ExecCommand
+	util.ExecCommand = rigtest.MockExecCommand
+	defer func() { util.ExecCommand = stashCommand }()
+	actual := util.GetDockerClientApiVersion()
+	rigtest.Equals(t, "1.30.0", actual.String())
+}
+
+// TestGetDockerServerApiVersion confirms successful Docker server version extraction.
+// For more thoroughly commented exec wrangling details see TestGetRawCurrentDockerVersion.
+func TestGetDockerServerApiVersion(t *testing.T) {
+	stashCommand := util.ExecCommand
+	util.ExecCommand = rigtest.MockExecCommand
+	defer func() { util.ExecCommand = stashCommand }()
+	actual, err := util.GetDockerServerApiVersion("gastropod")
+	rigtest.Ok(t, err)
+	rigtest.Equals(t, "1.30.0", actual.String())
+}
+
+// TestGetDockerServerMinApiVersion confirms successful Docker minimum API compatibility version.
+// For more thoroughly commented exec wrangling details see TestGetRawCurrentDockerVersion.
+func TestGetDockerServerMinApiVersion(t *testing.T) {
+	stashCommand := util.ExecCommand
+	util.ExecCommand = rigtest.MockExecCommand
+	defer func() { util.ExecCommand = stashCommand }()
+	actual, err := util.GetDockerServerMinApiVersion("gastropod")
+	rigtest.Ok(t, err)
+	rigtest.Equals(t, "1.12.0", actual.String())
+}
+
+// TestImageOlderThan confirms image age evaluation.
+// For more thoroughly commented exec wrangling details see TestGetRawCurrentDockerVersion.
+// @TODO identify how to mock the current time so we can test this more completely.
+func TestImageOlderThan(t *testing.T) {
+	stashCommand := util.ExecCommand
+	util.ExecCommand = rigtest.MockExecCommand
+	defer func() { util.ExecCommand = stashCommand }()
+	older, _, err := util.ImageOlderThan("outrigger/dust", 86400*30)
+	rigtest.Ok(t, err)
+	rigtest.Assert(t, older, "Image is older than 30 days ago but reporting as newer.", "howdy")
+}
diff --git a/cli/util/logger_test.go b/cli/util/logger_test.go
new file mode 100644
index 0000000..24d4ee9
--- /dev/null
+++ b/cli/util/logger_test.go
@@ -0,0 +1,18 @@
+package util_test
+
+import (
+	"testing"
+
+	rigtest "github.com/phase2/rig/cli/testing"
+	"github.com/phase2/rig/cli/util"
+)
+
+func TestLoggerInit(t *testing.T) {
+	util.LoggerInit(false)
+	logger := util.Logger()
+	rigtest.Assert(t, !logger.IsVerbose, "Logger initialized in Verbose mode.")
+
+	util.LoggerInit(true)
+	logger = util.Logger()
+	rigtest.Assert(t, logger.IsVerbose, "Logger initialized in non-Verbose mode.")
+}
diff --git a/cli/util/shell_exec_test.go b/cli/util/shell_exec_test.go
new file mode 100644
index 0000000..e29e4b0
--- /dev/null
+++ b/cli/util/shell_exec_test.go
@@ -0,0 +1,18 @@
+package util_test
+
+import (
+	"testing"
+
+	rigtest "github.com/phase2/rig/cli/testing"
+	"github.com/phase2/rig/cli/util"
+)
+
+// TestPassThruCommand confirms we receive the exit code.
+// For more thoroughly commented exec wrangling details see docker_test.go::TestGetRawCurrentDockerVersion.
+func TestPassthruCommand(t *testing.T) {
+	actual := util.PassthruCommand(rigtest.SuccessExecCommand("ls"))
+	rigtest.Equals(t, 0, actual)
+
+	actual = util.PassthruCommand(rigtest.FailExecCommand("ls"))
+	rigtest.Equals(t, 42, actual)
+}
diff --git a/cli/util/util_test.go b/cli/util/util_test.go
new file mode 100644
index 0000000..33b19fe
--- /dev/null
+++ b/cli/util/util_test.go
@@ -0,0 +1,14 @@
+package util_test
+
+import (
+	"testing"
+
+	rigtest "github.com/phase2/rig/cli/testing"
+)
+
+// Controls the test execution fo the util sub-package.
+// Note that if tests were to be run for the entire package cross-package
+// duplication of this function would cause it to explode.
+func TestMain(m *testing.M) {
+	rigtest.MainTestProcess(m)
+}